I love being able to update the contents of the carousel on demand; however, is there a way while updating the carousel with the external file, [stepcarousel.loadcontent('galleryid', 'path_to_file') ] to also jump to a predefined panel?

Notice the red. Those (except for the number) are the gallery id. They of course must all be the same. The number is the index of the panel that you want it to move to once the external content is loaded. The optional reset line may be removed. If it is, the carousel will always step to 3 whenever new content is added, unless something changes the oninit again. In other words, if all of your code loading external content first sets its own oninit, the reset isn't needed. In most cases you would want a reset or it would at least do no harm. Unless you're sure you don't need or want it, keep it.